The invention relates to a device for adjusting the height of a vehicle body.
Devices for adjusting the height of vehicle bodies are provided on the suspension struts of motor vehicles, in particular, for increasing the ground clearance of motor vehicles or, in the event of flat road surfaces, for reducing the ground clearance in order to improve the aerodynamic properties. Here, for example, according to EP 2 332 756 A2, height adjustment is provided between a mount of the suspension strut and an upper spring plate of a pretensioned spring of the suspension strut or, as known from EP 1 953 013 A2, between a component holding a wheel carrier, such as a sleeve part, and a lower spring plate. Such devices are actuated, for example, by an electric motor that rotationally drives a movement thread, for example, a spindle drive or ball spindle drive, so that, from the rotational movement, for example, a rotationally locked and axially displaceable spindle and a rotationally driven, axially fixed spindle nut carries out an axial displacement of a fixed component relative to a component of the suspension strut that can be axially displaced relative to this part and thus an essentially continuous height adjustment of the suspension strut and thus the vehicle body is achieved with a corresponding adjustment of the ground clearance between an upper and a lower adjustment position. In this arrangement, impacts absorbed by the wheel mounted on the suspension strut have a negative effect on the movement thread, in particular, on the balls and raceways of a ball screw drive.
From DE102014206142 A1, a known device is disclosed. The movement thread is bridged with a positive fit by a locking device. Here, for example, a locking ring with control cams is held so that it can rotate and is axially fixed on the spindle of the movement thread. The control cams are guided in guide grooves of a guide sleeve that is connected to the spindle nut and is designated below as a locking sleeve. The locking ring is rotated step by step after the locking cams leave the guide grooves by a ramp ring arranged axially fixed on the spindle nut for relative displacements between the locking ring and spindle nut in the sense of a ballpoint pen principle.
When the locking cams are lowered onto the locking stops, an axially positive-fit stop bridging the movement thread is formed. Here, the locking sleeve is provided in one piece with molded locking stops and guide grooves, so that these must each be designed separately for each application and according to customer requirements.